Open AccessEnhancement of postreplication repair in Chinese hamster cells.
Author(s) -
Steven M. D’Ambrosio,
R. B. Setlow
Publication year - 1976
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.73.7.2396
Subject(s) - chinese hamster , postreplication repair , cycloheximide , dna , microbiology and biotechnology , hamster , biology , dna repair , dna synthesis , 2 acetylaminofluorene , protein biosynthesis , chemistry , biochemistry , in vitro , nucleotide excision repair , microsome
Alkaline sedimentation profiles of pulse-labeled DNA from Chinese hamster cells showed that DNA from cells treated with N-acetoxy-acetylaminofluorene or ultraviolet radiation was made in segments smaller than those from untreated cells. Cells treated with a small dose (2.5 muM) of N-acetoxy-acetylaminofluorene or (2.5 J-m-2) 254-nm radiation, several hours before a larger dose (7-10 muM) of N-acetoxy-acetylaminofluorene or 5.0 J.m-2 of 254 nm radiation, also synthesized small DNA after the second dose. However, the rate at which this small DNA was joined together into parental size was appreciably greater than in absence of the small dose. This enhancement of postreplication repair (as a result of the initial small dose) was not observed when cells were incubated with cycloheximide between the two treatments. The results suggest that N-acetoxy-acetylaminofluorene and ultraviolet-damaged DNA from Chinese hamster cells are repaired by similar postreplicative mechanisms that require de novo protein synthesis for enhancement.